given and hindquarter muscle protein turnover and glutamine release were calculated in a three-compartment model. Results: Hysterectomy increased muscle protein breakdown in control rats with subsequent glutamine release. In TB animals, net protein breakdown and glutamine release was chronically increased and after surgery no fur- ther increase in protein breakdown nor glutamine release was observed. Control Tumour bearing Sham Hysterectomy Sham Hysterectomy Protein breakdown b'° 30-+4 86_+16 45_+11 42_+11 Proteinsynthesis 24_+2 44-+12 18_+11 13_+10 Glutamine release b'c 199 -+ 41 595 _+ 73 346 _+ 39 389 -+ 37 Mean -+SEM (nmol Phe or Gin x 100g bw -1 x min -1). Two-way ANOVA(P < 0.05); ~tumour effect; bhysterectomy effect;Cinteraction of tumour and hysterectomy. Conclusions: Surgical stress induces acute muscle protein breakdown mobilizing amino acids like glutamine for use by visceral organs and immune cells. The presence of cancer prohibits the normal proteolysis and glutamine release of muscle after surgery. This reduced metabolic response to surgery may affect the response of visceral organs and the immune system to postoperative metabolic stress. 7th Session - GASTROINTESTINAL SYSTEM 0.49 Prophylactic enteral administration of L-arginine improves the intestinal barrier function after mesenteric ischaemia Ren~ Schleiffer and Francis Raul CJF INSERM 95-09, IRCAD, 67000-Strasbourg, France. Ischaemia/reperfusion (i/R) of the intestine causes mucosal injury associ- ated with a high mortality rate in rats. Several data have shown that the inhi- bition of nitric oxide (NO) production exacerbates intestinal damage. The aim of the present study was to extend the possible contribution of NO in the regeneration of mucosal function by examining the effects of NO pro- duction on intestinal barrier permeability in the postischaemic intestine of adults rats. Methods: Wistar rats (350 g) were subjected to mesenteric artery occlu- sion for 90 min. The animals were given either L-arginine, the substrate of NO (0.8g/kg wt, n = 6) or the anti-anginal drug and NO donor mol- sidomine (Cassella AG, Germany) (12 mg/kg wt, n = 6). Controls received casein hydrolysate (0.8 g/kg wt, n = 6). The compounds were adminis- tered by gavage 19, 16 and 1.5 h before ischaemia. Mucosal barrier per- meability was assessed 24h after ischaemia by measuring the lumen-to-blood fluxes of labelled polyethylene glycol 4000 (14C-PEG, Amersham, UK). Since NO activates guanylate cyclase we determined also the mucosal content of cGMP. Results: Survival after I/R was 50% in the control group. Animals treated with L-arginine or molsidomine exhibited a higher survival rate (70% and 83%, reSpectively). Mucosal barrier permeability was significantly decreased in rats receiving L-arginine or molsidomine compared to con- trols (mean _+ SE: 4.0 + 0.8 and 2.6 _+ 0.6 versus 11.2 _+ 1.1 14C-PEG pmol/segment, P < 0.05). In the intestinal mucosa of rats treated with L- arginine, the cGMP content was significantly enhanced when compared with the molsidomine and control groups (mean _+SE: 103 _+ 1.0 versus 70 _+ 0.9 and 62 _+ 0.4 pmol/g mucosa, P < 0.01 ). Conclusions: The present findings suggest that pretreatment with exogenous sources of NO (L-arginine or molsidomine) ameliorates sur- vival after intestinal I/R and improves mucosal barrier function. We spec- ulate that increased NO formation or provision of exogenous NO may exert a beneficial effect by improving intestinal recovery from ischaemic insult. 0.50 The effect of nutritional depletion and parenteral nutrition on intestinal absorption and enzyme activity in man R. R. W. J. van der Hulst, B. K. van Kreelt, M. F von Meyenfeldt and P. B. Soeters of Surgery and Clinical Chemistry, Academic Hospital, Departments t Maastricht, The Netherlands. Total parenteral nutrition (TPN), resulting in gut starvation, is related to decreased villus height and increased intestinal permeability. Because the relative effect of nutritional depletion and TPN on intestinal aborption and nutrient digestion is not known, in this study the effect of TPN and nutritional depletion on xylose absorption and intestinal enzyme activities was assessed. Ten patients admitted for TPN were included in the study. Patients received TPN for a period of 2 weeks. Intestinal absorption and enzyme activities were studied before and after 2 weeks of TPN. A duodenoscopy was performed and biopsies from the second part of the duodenum were taken. A solution containing 5 g of xylose was administered into the duo- denal bulb at the end of the duodenoscopy. Plasma xylose was deter- mined in samples taken 1 h after administration of the solution. Additionally, xylose absorption and enzyme activities were determined in 12 nutritionally depleted patients and 10 non-depleted patients after an overnight fast. 1-h xylose Maltase Lactase Saccharase (mmol/I) (U/g) (U/g) (U/g) TPN day 0 0.6 (0.2-0.8) 262 (81-588) 42 (1-69) 69 (22-106) TPN last day 0.4 (0.2-0.6) 106 (16-213)* 13 (3-39)* 25 (2-63)* Non-depleted 0.6 (0.4-0.8) 252 (68-627) 29 (1-69) 65 (17-213) Depleted 0.7 (0.4-0.9) 168 (45-588) 30 (2-58) 35 (12-166) Median and ranges, * = P < 0.01, Wilcoxon. TPN resulted in a significant decrease in saccharase, lactase and mal- tase activity. Although xylose absorption decreased, this did not reach significance. Nutritional depletion was not related to a significant effect on xyiose absorption and enzyme activities. 0.51 Parenteral nutrition (PN)dependence factors in adult short bowel (SB) patients P. Crenn, P. Beau*, C. Matuchansky, J. C. Rambaud and B. Messing HSpital Saint-Lazar& Paris and *CHU de Poitiers, France. No quantitative data are available in the literature concerning parenteral nutrition (PN) dependence of adult SB patients and the factors involved. Methods: One hundred and twenty-four patients (61M, 63W, mean age 52 (17-85)) with SB (remaining small bowel length measured by opi- someter <150cm), constituted between 1 January 1980 and 30 June 1992, followed up in two hospitals with a home PN centre, were studied. Patients with small bowel reverse loop (n = 3), evolutive primary neopla- sia (n = 12) or other severe preexistent visceral deficiency (n = 2) were excluded. PN weaning was considered achieved if a well nourished or moderately malnourished status (according to Detsky, JPEN 1987) was achieved for at least 12 months following PN cessation. PN dependence probability, calculated from the last digestive circuit change, and judged on 30 October 1995, was expressed in actuarial curves according to Kaplan-Meier. The PN dependence factors were studied by univariate (log-rank test) and multivariate (Cox model) analysis. Results: Median (range) PN duration was 7 (0.5-160) months. Time period between the constitution of SB and the last digestive circuit change was 0-23 months, colonic continuity being achieved in 106 patients. 'Early' weaning, i.e. PN support <1 month after the last digestive circuit change, and 'late' weaning (PN > 1 month), was obtained in 34 (27%) and 30 patients (24%), respectively. PN dependence probability was 53% (CI95%: 44-62), 49% (40-58) and 45% (35-55) at 1, 2 and 5 years, respectively. Univariate analysis indicated that PN dependence probability was higher with small bowel remnant length <100cm, no ileo- caecal valve and no colonic remnant. Weaning was not associated with sex, age, SB aetiology and remaining small bowel lesions (n = 24). Multivariate analysis showed that small bowel remnant length (<50 cm, relative risk - RR - of 4.6 (1.9-11), 50-99cm: RR = 2.6 (1.5-4.6)), no colonic remnant (RR = 3.6 (1.1-11.7)) and no ileo-caecal valve (RR = 1.8 (1.1-3.2) were independent factors of PN dependency. Five-year survival probability of PN-dependent SB patients <60 years (n = 40) was 62 (47-77)%. 14